Refrigeration system



July R GRAYSON ETAL REFRIGERATION SYSTEM Filed April 9 1 930 4 Sheets-Sheet l u Ralph 1). Brag 5m: M a r. ia-1. 251

.Fufly 14, 1931. v GRAYSON L 1,814,915

REFRIGERATION SYSTEM Filed April 9, 1930 4 Sheets-Sheet 2 Ralph U. Eragsm & C .19. F125 Z22" ZZMMW July 14, 1931. R. v. GRAYSION ETAL Q 1,314,915

REFRIGEKATIONYSYSTEM Filed April 9 193 4 Sheats-Sh'et 5 l HI II I zzw m July 14, 1931. R v GRAYSON L 1,814,915

'" REFRIGERATION. SYSTEM Filed April 9, 193 4 Sheets-Sheet 4 SOURCE OF FBWER 5 EH4 I -R1ZZ h llfiraysan C. MHFUE Z22" Patented July 14, 1931 UNITED, STATES PATENT OFFICE RALPH V. GRAYSON, OF' MACON, AND CLAUD M. FOSTER, OF ATLANTA. GEORGIA, AS-

SIGNORS OF FORTY ONE-HUNDREDTHS TO POLAR PRODUCTS, INC., A. CORPORATION OF GEORG-IA I REFRIGERATION SYSTEM A lication filed. April 9,

This invention relates to refrigeration sys-' tems and applies particularly to the quick freezing-of bodies or masses such as foodstufi's. The invention concerns itself with the chilling of air to low temperature by passing it rapidly in closed circulation into heat exchangin relationship to the evapora:

tion element 0 the refrigerating system of the Carnot cycle type.

One of the objects of the invention is to provide a system as above described, lIi'Wl'llCh a plurality of tunnels for receiving the prodnot to be frozen are intercalated in parallel relation in the closed air circulation system,

and controlled in such a manner that one or more of said tunnels may be closed to the passage of chilled air, for the purpose of admitting or removing the articles to be frozen without wasting the cold air.

Another object of the invention is the provision of tunnels arranged in multiple as above described-and thermostatically controlled according to the temperature individual to the tunnels, for closing the respective tunnel or tunnelsto the circulation offrigid air upon the attainment in said tunnel or tunnels of a desired freezing point, thus to be simultaneously advanced into said flues and to abut against the end wallsthereof so as to act "as valves for isolating the tunnels 'singlyorin plurality from participation in the closed air circulation.

ob'ect of Still another the'inventien'is the provision of open. ended telesco 1c extensions for the tunnels, which when 1n posltion of abutment against the confronting-walls of -the flues, as above described, aline wlth doors 1930. Serial No. 442,884.

in said walls, giving access to the common chamber formed by said, tunnels and extensions, for introducing the obj ects to be frozen at one end and removing them at the other end, while the tunnel being served is isolated from the closed circulation system of air.

A still further objectof the invention is the combination, in a closed circulation system of the type described of a tier of trays,

adapted .to be disposed in the air current andso constructed and arranged as to divert a portion of the air and deflect and circulate it about the objects on the trays, which are to be frozen.

Other objects of the invention will appear as the following description of.a practical and preferred embodiment of the invention proceeds. 1

In the drawings in which the same characters of reference are used through the entire specification to denote similar parts:

Figure 1 is a longitudinal vertical section Y through a system embodying the present invention, an intermediate part being broken away;

Figure 2 is a horizontal section, part being broken away;

Figure 3 is an end elevation, part being broken away and shown in section, this section being taken along the line 33 of Fig-v ure 2; v Figure {l is a perspective of the sleeve or telescopic extension;

Figure 5 is a longitudinal section on a larger scale, showing the sleeve and its operating appurtenances at one end of the tunnel, the sleeve being shown in closed position, the section being taken along the line 5-.5 of

. Figure 3 Figure- 6 1s a cross section taken along the line 6-6 of Figure 5, indicating operating means for the sleeve;

Figure 7 is a cross section through a tunnel door along the line 7 7 of Figure 5;

Figure 8 is a view partly in section taken alongthe line- 8-8 of Figure 5, showing the sleeve operating mechanism;

Figure 9 is a diagrannnatic-view showing the electrical connections by means of which a the sleeve is effected and controlled;

Figure 10 is a plan view of one of the trays a corner thereof being broken away showing a portion of the under-lying tray;

Figure 11 is a side elevation of trays;

Figures 12 and 13 are vertical elevations, partly in section showing door latching mechanism; and

Figure 14 is a diametrical section through one of the door openings showing a door as it appears in closed position.

Referring now in detail to the several figures, the numeral 1 represents a double walled compartment or chamber, the space between the walls of which is preferably filled with insulation material such as cork. This comsuperposed partment or chamber is divided roughly into two parts, the lower part of which is occupied by a plurality oftie'rs of tunnels, each of which is designated by the reference character 2. That part of the chamber above the tunnels is left vacant except for the presence of a blower 3 preferably of the centrifugal type, and at least, the evaporation element a of a refrigeration system of the Carnot type. This space as shown in Figure 1, also contains the usual other elements of a Carnot refriger-' themselves form part of this conduit.

It will be noted from Figure 1 that the air follows an endless path, being drawn by the blower through the evaporation unit of the refrigerating system. and then forced into the flue 5 at theleft of Figure 1,, the air passing through the tunnels 2, emerging into the line 6 and being carried again through the evaporation element. By means of this recurrent circulation system, avery low temperature of the air may be obtained depending of course, upon the efliciency of the'Carnot refrigeration system and the particular refrigerant used therein. In the present instance, it is assumed that carbon dioxide is used as a refrigerant. r

The tunnels 2 are arranged in multiple as part of the circulation conduit, that is to say, the said tunnels are normally open at both ends and the air current divides itself when it reaches the advance ends of said tunnels passing equally through each of the tunnels.

The tunnels 2 are so controlled that any one or more of them may be closed at a time, and it is obvious that when this happens, the entire volume of circulating air must pass through the tunnels which remain open,

the tunnel, said rollers affording anti-friction means for advancing the trays which are fed in at the front or advance ends of the tunnels.

The tunnels are likewise formed with extensions ateach end in the form of rectangular sleeves 11 such as are shown in Figure 4, said extensions telescoping over the respective ends of the tunnels and being carried by anti-friction bearings 12. When the sleeves are extended, they abut against the respective end walls, of the chamber or compartment. The sleeves thus act as valves-and when they are in abutment against the front and rear walls the tunnel or tunnels associated therewith are for the'time isolated from the rest of the circulation system. It is noted in Figure that the sleeves 11 are open at both ends and Figure 1 shows that a door 13 is in alinement with each sleeve so that when the sleeves are in position to close the tunnel, articles to be frozen may be fed into the tunnel through the open ended. sleeve merely by removing the door 13 in the end wall of the compartment.

The sleeves are operated manually or thermostatically, and it is preferred that they be so operated as to simultaneously open or close the ends of the tunnels- Operating means for the sleeves is shown in Figs. 5, 6, 7, 8 and 9 and it will be noted thatbeneath each sleeve is a pair of spaced racks 16 in mesh with gears 17, the latter being carried on a. stub shaft 18, which also carries a worm wheel 19 meshing with a worm 20 suitably carried by operating rod or shaft 21. When the shaft is rotated in one direction, the worm rotates the worm wheel which in turn rotates the gear 17 and they in turn operate the racks 16 in one direction. When the direction of rotatihn of the shaft 21 is reversed, the direction of travel of the gears is reversed and the racks 16 travel in the opposite direction.

of chilled air thus concentrating the freezing effect of the entire air column upon the tunnels remaining open. In this. manner all of the tunnels are quickly brought to the same desired condition of low temperature.

In carrying out of this automatic phase of our invention, it is preferred'to locate in luv each tunnel, a thermally responsive device such as a bulb 22, of known construction, containing for instance, an expansible fluid which actuates a diaphragm switch 23. It is to be understood that these specific instrumentalities are merely exemplary and that any form of thermostatic control is within the purview of the invention.

The diaphragm switch closes one or the other of two circuits according to the direction in which the diaphragm is flexed, each circuit including a solenoid 24 or 25 respectively arranged in operative relation to gears 26 and 27 slidably mounted upon a shaft 28 continuously rotated through an electric motor 29. The gears normally have a neutral position determined for them by the springs 30 and 31, but when either of the gears is attracted by the solenoid, it goes into mesh with a ring gear 32 at the end of the shaft 21.

Thus the direction of rotation of the shaft 21 depends upon which of the two gears is in mesh with the ring gear 32. In one instance, the shaft 21 rotates to close the sleeves and in the other case, the sleeves being already closed, the shaft 21 rotates in a-direction to open them.

Figure 6* shows that the shaft 21 has two worms 20 and 33, the helices of said worms being arranged in an opposite direction so as to actuate in a reverse manner the gears 34 and 35 which operate the sleeves .at the opposite end of the tunnel. It will be understood therefore, that both sleeves move simultaneously to closing position or to open position.

It is ofv course, obvious that when the sleeves have come into position of abutment with the end walls of the chamber or compartment, it is essential that means he provided to deenergize the solenoids so as to quickly restore whichever of the gears maybe in mesh with the ring gear 32, to neutral position. This is provided for in the present invention by contact switches 36 and 37 disposed at opposite endsof the range of travel of the sleeve andadapted to be contacted by the sleeve in either of its extreme positions. The contact switches each comprise contacts 38 and 39 normally ke t closed by means of a spring 40, butcapallle of being opened when one of the contacts is engaged by the adjacent end of the sleeve.

It will be observed from the circuit diagram shown in Figure 9 that the solenoid circuits each include two gaps, one aflorded by the diaphragm switch 23 and the other by the contact switch 36, and that the gap at the contact switch 36 is normally closed. Thus when the diaphragm switch moves to close its gap in one or the other direction, the gap at the contact switch is already closed and the circuit is therefore, completed and the solenoid energized, but when the sleeve reaches its limit of movement in one or the other directions, it engages the adjacent contact line.

switch, opening the same and thus provides a gap in the solenoid circuit, even though the diaphragm switch remains closed. Thus the solenoid circuit will be opened and the gears be permitted to spring to neutral position. It is to be understood that the diagram in Figure 9 suggests that the current for the solenoid circuit be tapped from the power The use of a transformer in the solenoid circuit for stepping down the voltage would of course, not amount to invention, being old practice. v

It is noted from Figure 5 that the tunnels are double-walled and that except for the reservation of the space for the necessary movement of the sleeves and their actuating mechanism, the jackets afforded by the double walls are lagged with cork or other suitable insulating material.

The products to be frozen are introduced through openings 41 in one of the end walls of the compartment, the said openings being closed by doors 42. When it is desired to charge any one or more of the-tunnels withthe material to be frozen, the shaft 21 may be manually operated so as to bring the sleeves simultaneously into position of abutment with respect to the end walls of the compartment 1. This manual actuation may be provided by means such as the bevel gear 44, having a polygonal boss 45 adapted to be engaged by a hand crank. When the sleeves have been moved to closed position, the door 42 is opened, the tunnel being at this time isolated from the general circulation of refrigerating air, and the common chamber formed by the tunnel and its extended sleeves, provides a continuous passage into which the articles to be frozen ma be introdguced and advanced along the be of rollers The doors 42 'are preferably closedwith a sealing fit, the doors being provided by means such as the crank {17 which reacts against hooks 48 diametrically placed with respect to the door, when the handle 49 is moved to the closing position shown in Figure 12. l

A wear piece 50-bears against the door and acts as a fulcrum for the crank 47. The 'm'ateone side of the tray is a series of bafiles 52. I

inclined in such manner when the tray is in- A troduced into the closed air circulation the baflies divert a portion of the air current causing it to flow inwardly upon the articles to e frozen. The trays are preferably formed with bafiies on one side only, and the baflies of one tray extending in the opposite direction to the bafies of another tray. The trays are arranged in tiers alternately with the bafiles on opposite sides. Figure has the corner broken away to show an underlying tray 53.

It will be noted-that while the bafiies of the tray 52 tend to entrain and divert a portion of the refrigerating air, the baffles of the under-lying tray are directed rearwardly with respect to the direction of the air current so that the said air current has a suction effect upon said baiiles. The aggregate result of the two sets of baflies is that the air is drawn in to one tray, passes around the articles on that tray and then downwardly through said tray on the articles of the next tray from-which it is drawn out by the baffles of the under-lying tray.

' The trays may be stacked to any desired height, according to the vamount of material to be frozen and the height dimension of, the

' tunnel. It is noted that the bank of rollers 9 extending through the tunnels, are inclined slightly downwardly to the discharge end of the tunnels, thus facilitating the feeding of trays continuously into said tunnels by pushing one tray against another, the resistance to movement, of the trays already within the tunnel being diminished by gravity.

Since the doors 42 may be of massive construction, we have indicated a pulley and tongs 58 which may be engaged with said doors for removing them or restoring them to position. This however, is a detail immaterial to the scope of the invention.

While we have in the above description defined what we believe to be a preferred and practical embodiment of our invention, it is to be understood that the details of construction are simply by way of example and not to be. considered limitative in their bearing tinuous conduit for the closed circulation of refrigerative air, including a refrigerating unit, a plurality of horizontal tunnels arranged in parallel insaid system with their ends communicating with vertical limbs of said system, a blower for forcing said refrigeratedair through said tunnels, and selectively operable means for excluding any tunnel or tunnels from said circulation system.

3. Refrigeration system comprising a con tinuous conduit for the closed circulation of refrigerative air, including a refrigerating unit, a plurality of substantially horizontal. tunnels arranged in parallel in said system with their ends communicating with' vertical conduits, doors in the outer walls of said conduits, a blower for forcing refrigerated air through said tunnels, and selectively operable means for excluding any tunnel or tunnels at both ends from said circulation system, and placing the ends of said excluded tunnels in communication with the outside of said system by way of said doors.

4. Refrigeration system comprising a continuous conduit for the closed circulation of refrigerative air, including a refrigerating unit, a plurality of horizontal tunnels arranged in parallel in said system with their ends communicating with vertical limbs of said system, a blower for forcing refrigerated air through said tunnels, and selectively operable means for excluding any tunnel or tunnels at both ends from said circulation system, said means including open ended sleeves forming part of said tunnels.

5. Refrigeration system comprising a continuous conduit for the closed circulation of refrigerative air, including a refrigerating unit, a plurality of tunnels arranged in parallel in said system, a blower for forcing refrigerated air through said tunnels, and

selectively operable means for excluding any tunnel or tunnels at both ends from said circulation system, said means including open ended sleeves forming part of the conduit within said tunnels, the latter communicating with said system by means of ports positioned to be occluded by said sleeves.

6. Refrigeration system comprising a continuous conduit for the closed circulation of refrigerative air, including a refrigerating unit, a plurality of horizontal tunnels ar- 'ranged in parallelin said system with their verting an increased proportion of the refrigerative flow through the tunnels remain-j ing open.

In a refrigeration system, a tunnel 'hav ing opposite open ends confronting flues forming part of a recurrent cold air circulation system, open ended extensions at oppos1te ends of sa1d tunnels and telescopic with respect thereto, advanceable into positions of abutment with" respect .to the far sides of said flues, means for so advancing said ex tensions to isolate said tunnel from said fines, and doors in the farsides of said-fines in the areas circumscribed by the abutting ends of extensions.

8. In a refrigeration system, a tunnel formingpart of'a closed conduit determining the path of recurrent circulation of cold air, means for producing a circulation ofcold air in said conduit, and a tray stack in said conduit having baflles at opposite sides directed respectivley for and aft relative to said air current, whereby air is inducted into said tray stack by one set of bames' and educted by the suction effect of the other set.

9. A tray stack for diverting cold air from a cold air current into intimate cooling relation to the contents of said tray stack, comprising open bottomed trays each having inclined baflles on one side, said trays being arranged alternately with their bafies at opposite sides so that the bafiles at opposite sides of the stack open respectively 'fore and aft relative to air current, whereby air is inducted into said stack by one set of baflies and educted by the suction efi'ect of the other set of baffles.

10. The method of induct-ing cold air from a cold air current and bringing it into intimate cooling relation to objects on a plu rality of similar open bottomed trays having inclined baflles .on one side only, comprising: stacking the trays alternately with the 'baflles at opposite sides and positioning the stack in the air current so that cold air is inducted into one tray by baflies on one side of the stack, passes to. the next lower tray, and is educted by the suction effect of the bafies in the opposite side.

In testimony whereof we afix our signatures.-

, RALPH V. GRAYSON.

CLAUD M. FOSTER. 

